‘We want to reinvent the toilet so it doesn’t need water piped in or out — just a chemical process so that even Indian cities that will never spend $1 billion can have a toilet as good as a Western one,’ he told The New York Times.

‘This is a 10-year quest.’

Through the Bill and Melinda Gates Foundation, the billionaire has donated millions to inventors working to build futuristic khazis as part of a scheme called ‘Reinvent the Toilet Challenge’.